Search Results - "de Melo, J. Sérgio Seixas"

Excited-State Proton Transfer in Indigo by Pina, J, Sarmento, Daniela, Accoto, Marco, Gentili, Pier Luigi, Vaccaro, Luigi, Galvão, Adelino, Seixas de Melo, J. Sérgio

“…Excited-state proton transfer (ESPT) in Indigo and its monohexyl-substituted derivative (Ind and NHxInd, respectively) in solution was investigated…”
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Deep in blue with green chemistry: influence of solvent and chain length on the behaviour of N - and N , N '- alkyl indigo derivatives by Pinheiro, Daniela, Pineiro, Marta, Galvão, Adelino M, Seixas de Melo, J Sérgio

“…Using green chemistry procedures the synthesis of -alkyl (NC Ind) and , '-dialkyl (N,N'C Ind) indigo derivatives, with = 1-3, 6, 8, 12 and 18, was undertaken,…”
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Multifaceted Regioregular Oligo(thieno[3,4‑b]thiophene)s Enabled by Tunable Quinoidization and Reduced Energy Band Gap by Liu, Feng, Espejo, Guzmán L, Qiu, Shuhai, Oliva, María Moreno, Pina, João, Seixas de Melo, J. Sérgio, Casado, Juan, Zhu, Xiaozhang

“…Thiophene-based materials have occupied a crucial position in the development of organic electronics. However, the energy band gaps of oligo- and…”
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Tuning J‐aggregate Formation and Emission Efficiency in Cationic Diazapentacenium Dyes by Rodrigues, Ana Clara B., Wetterling, Dario, Scherf, Ullrich, Seixas de Melo, J. Sérgio

“…Enhancement of the luminescence efficiency of two new diazapentacenium salts (D1 and D2) of more than 55 for D1 and 22 times for D2) in poor solvents,…”
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Excited-State Dynamics and Self-Organization of Poly(3-hexylthiophene) (P3HT) in Solution and Thin Films by Ferreira, Bruno, da Silva, Palmira Ferreira, Seixas de Melo, J. Sérgio, Pina, João, Maçanita, António

“…The fluorescence decays of a stereoregular head-to-tail RR-HT poly(3-hexylthiophene), P3HT, in methylcyclohexane (MCH) are described by sums of three or four…”
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Interactions and Supramolecular Organization of Sulfonated Indigo and Thioindigo Dyes in Layered Hydroxide Hosts by Costa, Ana L, Gomes, Ana C, Pereira, Ricardo C, Pillinger, Martyn, Gonçalves, Isabel S, Pineiro, Marta, Seixas de Melo, J. Sérgio

“…Supramolecularly organized host–guest systems have been synthesized by intercalating water-soluble forms of indigo (indigo carmine, IC) and thioindigo…”
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Effect of Co Doping on the Physical Properties and Organic Pollutant Photodegradation Efficiency of ZnO Nanoparticles for Environmental Applications by Saadi, Hajer, Khaldi, Othmen, Pina, João, Costa, Telma, Seixas de Melo, J Sérgio, Vilarinho, Paula, Benzarti, Zohra

“…This paper presents a comprehensive investigation of the synthesis and characterization of Zn Co O (0 ≤ x ≤ 0.05) nanopowders using a chemical co-precipitation…”
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Reconstructing the historical synthesis of mauveine from Perkin and Caro: procedure and details by Cova, Tânia F. G. G., Pais, Alberto A. C. C., Seixas de Melo, J. Sérgio

“…Mauveine, an iconic dye, first synthesised in 1856 still has secrets to unveil. If nowadays one wanted to prepare the original Perkin’s mauveine, what would be…”
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Brazilwood Reds: The (Photo)Chemistry of Brazilin and Brazilein by Rondão, Raquel, Seixas de Melo, J. Sérgio, Pina, João, Melo, Maria J., Vitorino, Tatiana, Parola, A. Jorge

“…The ground and excited state (in the singlet state, S1) acid–base equilibria, together with the photophysical properties of the two main constituents of…”
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Aggregation-Induced Emission in Phenothiazine–TPE and −TPAN Polymers by Rodrigues, Ana Clara B, Pina, João, Dong, Wenyue, Forster, Michael, Scherf, Ullrich, Seixas de Melo, J. Sérgio

“…Two phenothiazine-based polymerstetraphenylethylene- (PTzTPE) and triphenylacrylonitrile-substituted (PTzTPAN) polyphenothiazineswere studied in organic…”
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Aggregation-Induced Emission with Alkynylcoumarin Dinuclear Gold(I) Complexes: Photophysical, Dynamic Light Scattering, and Time-Dependent Density Functional Theory Studies by Cunha, Carla, Pinto, Andrea, Galvão, Adelino, Rodríguez, Laura, Seixas de Melo, J. Sérgio

“…Aggregation-induced emission (AIE) has gained a remarkable amount of interest in the past 20 years, but the majority of the studies are based on organic…”
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Red-Purple Photochromic Indigos from Green Chemistry: Mono‑tBOC or Di‑tBOC N‑Substituted Indigos Displaying Excited State Proton Transfer or Photoisomerization by Pinheiro, Daniela, Galvão, Adelino M, Pineiro, Marta, de Melo, J. Sérgio Seixas

“…In indigo, excited state proton transfer (ESPT) is known to be associated with the molecular mechanism responsible for highly efficient radiationless…”
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Dehydroindigo, the Forgotten Indigo and Its Contribution to the Color of Maya Blue by Rondão, Raquel, Seixas de Melo, J. Sérgio, Bonifácio, Vasco D. B, Melo, Maria J

“…A comprehensive investigation of the electronic spectral and photophysical properties of the oxidized form of indigo, dehydroindigo (DHI), has been carried out…”
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Aggregation‐Induced Emission Leading to White Light Emission in Diphenylbenzofulvene Derivatives by Rodrigues, Ana Clara B., Peixoto, Mariana, Gomes, Carla, Pineiro, Marta, Seixas de Melo, J. Sérgio

“…The search for a unique molecular system able to efficiently emit in the total visible range of the electromagnetic spectra, i. e., white light emission (WLE),…”
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Comprehensive Investigation of the Photophysical Properties of Alkynylcoumarin Gold(I) Complexes by Pinto, Andrea, Cunha, Carla, Aullón, Gabriel, Lima, João Carlos, Rodríguez, Laura, Seixas de Melo, J. Sérgio

“…Six gold­(I) complexes (R3P-Au-Coum) containing three different alkynylcoumarin chromophores (Coum) with different electron-donating and electron-withdrawing…”
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Deactivation Routes in Gold(I) Polypyridyl Complexes: Internal Conversion Vs Fast Intersystem Crossing by Aguiló, Elisabet, Moro, Artur J, Outis, Mani, Pina, João, Sarmento, Daniela, Seixas de Melo, J. Sérgio, Rodríguez, Laura, Lima, João Carlos

“…An electronic spectral and photophysical characterization of three gold­(I) complexes containing heterocyclic chromophores differing in the number and…”
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Tuning the Behavior of a Hydrotalcite-Supported Sulfonated Bithiophene from Aggregation-Caused Quenching to Efficient Monomer Luminescence by Delgado-Pinar, Estefanía, Costa, Ana L, Gonçalves, Isabel S, Pineiro, Marta, Pillinger, Martyn, Seixas de Melo, J. Sérgio

“…The synthesis, electronic spectral, and photophysical properties of a new bithiophene derivative, (2,2′-bithiophene)-3,5,5′-trisulfonic acid, α2-SO3H, were…”
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Cationic Diazapentacenium Polymers Made in a Sequence of CN Cross Coupling Polymerization and Acid‐Mediated Postpolymerization Cyclization by Wetterling, Dario, Forster, Michael, B. Rodrigues, Ana Clara, Seixas de Melo, J. Sérgio, Scherf, Ullrich

“…Polycationic stepladder polymers containing 5,12‐diazapentacenium bistriflate repeat units are made in a two‐step sequence of a carbon‐nitrogen cross coupling…”
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Understanding the Interaction between Trivalent Lanthanide Ions and Stereoregular Polymethacrylates through Luminescence, Binding Isotherms, NMR, and Interaction with Cetylpyridinium Chloride by Kogej, Ksenija, Fonseca, Sofia M, Rovisco, José, Azenha, M. Emília, Ramos, M. Luísa, Seixas de Melo, J. Sérgio, Burrows, Hugh D

“…Complexation of isotactic, syndiotactic, and atactic poly(methacrylic acid), PMA, with trivalent lanthanide ions has been studied in water at a degree of…”
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Synthesis and Characterization of the Ground and Excited States of Tripodal-like Oligothienyl-imidazoles by Pina, João, Seixas de Melo, J. Sérgio, Batista, Rosa M. F, Costa, Susana P. G, Raposo, M. Manuela M

“…Six new thiophene oligomers, here designated as tripodal-like oligothienyl-imidazoles, were synthesized and have been investigated in ethanol solution at room…”
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